Chemical composition and insecticidal activity of essential oil of Artemisia herba alba (Asteraceae) against Ephestia kuehniella (Lepidoptera: Pyralidae)

Plant secondary metabolites play an important role in plant-insect interactions and therefore such compounds may have insecticidal or biological activity against insects. In the present study, aerial parts of Artemisia herba alba Asso were subjected to hydro distillation using a Clevenger-type apparatus and the chemical composition of the volatile oils was studied by GC-MS. Forty two compounds were detected. The main components of the essential oil were D-camphor (34.34%), Eucalyptol (13.49%), α-thujone (8.37%), Camphene (8.26%), Chrysanthenone (6.40%), Isoborneol (5.94%), β thujone (4.24%). Insecticidal activity of the oil was evaluated for Ephestia kuehniella. The essential oil was tested with various amounts (1, 3 and 5 ml/ml of acetone) on the adults of E. kuehniella; this oil present an insecticidal activity and induce in the females of insect a very significant reduction of the laying compared with that in the control. In addition, eggs hatching rate laid by treated females is reduced. It will be interesting to test theses essential oils in situ to assess their efficiency in the conservation of stored food.